Ingredient review
Diglycerin/Dilinoleic Acid/Hydroxystearic Acid Copolymer
INCI: DIGLYCERIN/DILINOLEIC ACID/HYDROXYSTEARIC ACID COPOLYMER
A gentle film-forming polymer that improves water resistance and texture in sunscreens and lotions without clogging pores.
In plain English
This ingredient is a type of polymer (a long chain of molecules) made from glycerin and fatty acids. In skincare, it creates a thin, flexible film on your skin that helps other ingredients stay put and resist washing off with water or sweat. It also makes creams and lotions feel silky and spread more evenly.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Diglycerin/Dilinoleic Acid/Hydroxystearic Acid Copolymer is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Diglycerin/Dilinoleic Acid/Hydroxystearic Acid Copolymer.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A semi-synthetic copolymer formed by linking diglycerin (a humectant derived from glycerin) with dilinoleic acid and hydroxystearic acid (both fatty acids from plant oils). The result is a large molecule that acts as a film former and texture enhancer.
How it works
When applied, the copolymer forms a uniform, breathable film over the skin. This film helps sunscreen actives stay evenly distributed and resist water, and it gives lotions a smooth, non-greasy feel. It also slightly thickens the product, making it easier to spread.
Pros
Boosts water resistance
Helps sunscreens and makeup stay effective longer during swimming, sweating, or humid conditions.
Silky, non-greasy feel
Creates a smooth, velvety texture on skin without the heavy, oily residue of some emollients.
Cons and cautions
Not moisturizing
It forms a film but does not add moisture to the skin, so it works best paired with humectants or emollients.
Can feel tacky in high amounts
In formulas with a high concentration, some users may notice a slight sticky or tight feeling as the film dries.
Best for
- People who want water-resistant sunscreens or long-wear makeup
- Those with normal to oily skin who prefer a non-greasy finish
Use caution if
- People with very dry skin who need heavy emollients may find it insufficient alone
Usage tips
Safety summary
Considered safe for topical use with very low irritation and comedogenic potential. No significant safety concerns reported in cosmetic concentrations.
Research notes
Limited peer-reviewed studies specifically on this copolymer, but related film-forming polymers have been shown to be safe and effective for water resistance and texture improvement in cosmetics.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics globally, including by the FDA (as a cosmetic ingredient) and EU CosIng database. No concentration restrictions for typical use.
- Common uses
- Sunscreens, Water-resistant lotions, Long-wear makeup, Moisturizers
- Environmental note
- As a synthetic polymer, its biodegradability is limited. However, it is not known to bioaccumulate significantly. Some brands are moving toward biodegradable alternatives.
Good to know
- This ingredient is often used in 'water-resistant' sunscreens and is considered safe for daily use.
- It is not a sunscreen active itself, so it won't provide UV protection on its own.
Common questions
What is Diglycerin/Dilinoleic Acid/Hydroxystearic Acid Copolymer in beauty products?
This ingredient is a type of polymer (a long chain of molecules) made from glycerin and fatty acids. In skincare, it creates a thin, flexible film on your skin that helps other ingredients stay put and resist washing off with water or sweat. It also makes creams and lotions feel silky and spread more evenly.
What does Diglycerin/Dilinoleic Acid/Hydroxystearic Acid Copolymer do in a beauty product?
When applied, the copolymer forms a uniform, breathable film over the skin. This film helps sunscreen actives stay evenly distributed and resist water, and it gives lotions a smooth, non-greasy feel. It also slightly thickens the product, making it easier to spread.
Is Diglycerin/Dilinoleic Acid/Hydroxystearic Acid Copolymer safe for most people?
Considered safe for topical use with very low irritation and comedogenic potential. No significant safety concerns reported in cosmetic concentrations.
Who should be careful with Diglycerin/Dilinoleic Acid/Hydroxystearic Acid Copolymer?
People with very dry skin who need heavy emollients may find it insufficient alone
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.